Method of purifying petroleum hydrocarbons



Patented Feb. 2, 1932 an east ALFRED OBE RLE, OF KANSAS CITY, MISSOURI, ASSIGNOR F ONE-HALF T0 THOMAS E.

Y V SGOFIELD, OF KANSAS CITY, MISSOURI METHOD or rnnrnyrna rnrnonnnm HYnnooAnBons No Drawing.

' This invention relates to improvements in a method for purifying petroleum hydrocarbons, and refers more particularly' to a method for decolorizing," deodorizing and oompa'sses'any type of petroleum hydrocar- H bons.

This invention is a continuation in an'application Serial No. 7 53,345, filed December 1st, 1924.

Among the objects of the invention are, to provide a method in which petroleum preferably iodine, this material being used in the purificationof the oil as a watersoluble material or in a Water solution or partially so; to provide a process in which a halogen such as iodine is made watersoluble and the solution used for thepurific'ation of the oil while the latter is either in the liquid or vapor phase as may also be the Purifying material; to provide a process which effec- 'tively removes from hydrocarbon oils objectionable impurities, permanently decolmining the oil and eliminating sulphur compounds and other impurities tending to effect the marketability of the ultimate prod not; to provide a process which, in addition to its purifying qualities, lends .to the purifled oil improved characteristics in the way of producing a material which improved qualities when used as a motor fuel particularly, with reference to its anti-knock properties, and, in general, to provide a process hereinafter described inmore detail.

While the halogen is adaptable for the purification of any type of hydrocarbon material, it is particularly adapted to those petroleum distillates which result from'the pressure decomposition or cracking of oils,

' such oils being particularly objectionable as to odor, color and their gum forming prop-- erties.

It has been found that distillate, such as above mentioned and particularly lighter oilsrecovered from petroleum by pressure distillation, are very apt to go off color by exposure to light. This tendency is particu- "part of hydrocarbons are purified with a halogen,

odorless and sweet, and remains so.

Application filed March ll, 1226. Serial No. 94,052.

larly noticeable where gasoline is exposed in visible pumps, to sunlight, or artificial light.

Numerous methods and processes have been attempted to eliminate the objectionable characteristics of cracked distillates in the way of steam distillation, acid and caustlc treatments, or treatment with sulphur diox ide, sodium plumbite, fullers earth, charcoal fillers, silica gel, etc. All of these processes are more or less eflec'tive but most of them are particularly objectionable due to the waste or loss which attends the purifying treatment.

" Ithas been found that, when a distillate is. treated or Washed with anaqueous solution.

containing iodine, the distillate, upon'exposure to conditions which would normally tend to cause it to go off color, has this characteristic offset by the treatment to the extent that it may stand indefinitely while being subjected to such conditions Without discoloration. There is a gravitational separation'wliich takes place, leaving the purified oil easily separable from thepurifying material. After separation from the aqueous iodine solution, the distillate is filtered, at which time the color is substantially re moved. With a subsequent'water wash, the resulting product is found to be Water white,

The aqueous solution containing iodine separated from the treated oil may be reused in the form in which it is recovered or after under going a purifying treatment to eliminate the,

impurities gathered from the oil. It has been found from actual experimentation that this treatment in the presence of sunlight, artificial light or in the presence of ultraviolet rays, is perceptibly activated and improved.

These iodine compounds may be used as a purifying material in the form of solids or mixtures of solids, also as liquids or mixtures of liqu'ids,an' example of which would be iodine in solution with a liquid other than Water or With Water. Further methods of combination are in the form of aqueous solution containing iodine as previously described, or mixtures of aqueous solutions containing iodine. Either of the above methods of treating with iodine may be used to treat the oil either in the liquid or in the vapor phase, depending primarily upon the temperature of treatment. The period of treatment or the time factor necessary to produce the treatment desired will depend to a great extent upon the character of the oil undergoing treatment and the particular iodine compound used. Under certain conditions, also, it has been found to improve the method of treatment by using pressure above atmospheric, and in other cases the process is rendered more effective by the use of a vacuum. Normal treatment may be produced at atmospheric conditions. Ithas been found that the iodine treatment gives certain characteristic colors'with difierent types of oils, i. e.,

different types of oils treated with the same purifying material will give difi'erent characteristic colors. Likewise,diiferent iodine I compounds when treating the same oil may give different characteristic colors, the colors ranging from a light yellow to a dark blue violet,depending upon the iodine compound utilized .or upon the characteristic oil being treated and also more or less upon the degree of exposure to light. I

The normal treatment-of petroleum distillates'for' purification has a tendency to remove from the oil certain desirablecharacteristics in the oil which have a tendency to improve its anti-knock qualities. As contrastedwith this normal treatment, the iodine treatment herein described has an opposite.

tendency, i. e., it. improves the anti-knock qualities in place of diminishing such properties in the oil. In this connection it is of interest to note that the coloring in some of the treated oils has a direct bearing or relation upon its anti-knock properties. When it is of importance to procure a motor fuel having improved anti-knock properties, it may be advisable to somewhat: restrict the elimination of color as under certain conditions the producing of a water-white product may, to a more or less extent, diminish the anti-knock properties.

Among the compounds of iodine adaptable to this purifying treatment are those of: potassium, sodium, ammonium, barium, strontium, lead, calcium, cadmium, copper, magnesium, manganese, mercury, nickel, rubidium, silver, tellurium, tin, zinc.

Some of these compounds are especially adaptable. Each of these substances in com bination with iodine has its characteristic solubility which may be increased or decreased by the addition and combination with other substances. Thus, potassium iodide and iodoeosin are readily water soluble, while mercuric iodide is relatively insoluble but is rendered easily soluble by the addition of potassium iodide or calcium iodide thereto- In the same manner other compounds such as iodide compound of lead which is relatively insoluble, having a solubility of about-099 glass wool, glass beads, steel wool or other material which insures intimate contact between the vapors and purifying solution. In the liquid phase, the purifying solution is combined and intimately mixed by agitation so as to distribute or thoroughly commingle the purifying solution and the oil. Where it is found advantageous to have both the purifying material and the oil in the vapor phase,

any of the well known methods of mixing and 8 subsequent separation by gravitational separation and condensation may be adapted. Counterflow methods are also effective in this connection.

l claim'as my invention:

V 1. A process for altering the characteristics of cracked petroleum hydrocarbons in the way of purification and improving their antidetonatingproperties comprising contacting the hydrocarbons in vapor-phase with -&I1"9 aqueous solution of an iodine salt.

2. A. process for altering the characteristics of cracked petroleum:hydrocarbons in the way of purification and improving their antidetonating properties comprising contacting the hydrocarbons in vapor-phase with an aqueous solution containing a plurality of metallic iodides.

3. A process for altering the characteristics the purifying material which may contain of cracked petroleum hydrocarbons in the way of purification and improving tlieir antidetonating properties comprising the steps-of treatingthe oil in the vapor-phase withian aqueous solution of iodine compounds and separating from the oil the treating material insoluble in the hydrocarbons.

4. A process for altering the characteristics of cracked'p'etroleumhydrocarbons-in the way of purification and improving their antidetonating properties comprising the steps of treating the oil in the vapor-phase with a mixture of iodine compounds in aqueous solution and separating from the oil any excess of the treating material.

ALFRED OBERLE. 

